Process for preparing nuclear-substituted arylsulphonic acids



Patented May 13, 1930 UNITED STATES PATENT orrics OBS TO I. G. FARBENINDUSTRIE AKTIENGESELLSCHAFT, OF .FRANKIOBT-ON-THE- MAIN, GERMANY, A CORPORATION OF GERMANY rnocsss'ron ranramne NUCLEAR-SUBSTITUTED ARYLSULPHONIO ACIDS no Drawing. Application filed March 16, 1927, Serial No. 175,827, and in Germany larch 27, 1928.

The present invention relates to a process of preparing aryl-polysulfonic acids which are substituted by at least one alkyl group having more than two carbon atoms and to new compounds obtainable thereby.

In our copending application Serial No. 95,770, filed March 18, 1926, there is described a process of preparing substituted arylpolysulfonic acids, which comprises treating a mixture of an aromatic hydrocarbon and an alcohol of higher molecular weight than ethyl alcohol with a stronger sulfonating agent than sulfuric acid monohydrate.

We have now found that one may use in this process as starting material instead of the aromatic hydrocarbon a sulfonic acid of an aromatic hydrocarbon, provided that the said sulfonic acid compound is used in an utmost anhydrous state. This condition can best be fulfilled by using a sulfonicacid which has been prepared by means of chlorosulfonicac d, or a suli'onic acid which, though obtained by means of sulfuric acid, has subsequently been freed from the water by heat or, if required, by evacuation or any other method. By thus employing finished anhydrous sulfonic acids instead of unsulfonated hydrocarbons. it is possible to obtain variations regarding the position of the sulfo groups; for instance in the preparation of naphthalene derivatives a simultaneous sulfonation in the a and B-position in contrast with the sulfonat on as referred to in our said pending application which occurs almost exclusively in oz-POSltlOIl or wot-position. These variations may involve an important advantage for certain purposes for which the arylsulfonic acids in question are to be used.

The following example serves to illustrate our invention, but it is not intended to limit the invention thereto.

lnto 1280 parts of molten naphthalene are introduced at l35l4l5 C. 1200 parts o'f chlorosultoni'c acid: this mixture is stirred for some. time. cool-(d down to 70 C. and there are then slowly run into it at 70 C. 800 parts oi butyl alcohol and at the same t me 00 parts of chlorosulionic acid. After some hours. there are again run into the n'iixture 4 0 parts of chlorosulfonic acid. As soon as the producthas become entirely soluble in water, it is worked up into its dry sodium salt. The yield amounts to about 3600 kilogrammes, the product being a light-colored powder, which is readily soluble in water and which can be used with particular advantage as a wetting thelike. p

We claim: '1;

1-.' The process of reparin aryl-polysulfo'nic acids whic comprises treating .a mixture of an aromatic hydrocarbon sulfonic acid compound which is in a completely dry form and an alcohol of higher molecular welght than ethyl alcohol with a stronger sulfonating agent than sulfuricacid monohydrate.

2. The process of reparin substituted aryl-polysulfonic aci s whic comprises treating a mixture of an aromatic hydrocars bon sulfonic acid compound which is in a completely dry form and an alcohol of higher molecular weight than ethyl falcoholiwith chlorosulfonic acid.

3. The process which comprl ing about 1280 parts of molten naphthalene into 1200 parts of chlorosulfonic acid at a temperature of about 135 to 145 0., cooling the mixture to about 70 0., adding then at a temperature of about 60 to about 70 C. about 800 parts of butyl alcohol and about 600 parts of chlorosulfonic acid, after some hours adding 400 additional parts of chlorosulfonic acid and causing the reaction components to act upon each other until the reaction product has become soluble in water.

4. As a new product a naphthalene polysulfonic acid compound which is substituted by at least one alkyl group having more than two carbon atoms and which has at least one of the (it-positions and at least one of the [3- positions substituted by a sulfonic acid group.

5. Asa new product a butyl-naphthalene sulfonic acid compound which is substituted in at least one of its a-positions and in at least one of its ,3-positions by a sulfonic acid group.

In testimony whereof, we aflix our signatures.

KARL DAIMLER. GERHARD BALLE.

agent, an emulsifying agent or substituted I 

